摘要:
A nematic liquid crystal device for electro-optical display devices, is provided. Its long-shaped molecules are orientated perpendicularly to the electrode plates delimiting the crystalline liquid, i.e. homeotropically aligned. A polymer layer with long-chain molecules has been previously formed on the internal faces of each plate separately arranged on a discharge electrode of an electrical apparatus operating at high frequency (13.56 mc/s) and containing a vapour at very low pressure of a monomer such as hexamethyldisiloxane. The molecules of polymer thus formed are perpendicular to the plates and a similar orientation of the liquid crystal molecules result from that, i.e. a homeotropic alignment.
摘要:
The polymer material is made from a first monomer and from a second monomer. The first monomer Ar includes at least one aromatic nucleus and the second monomer is a five links conjugated heterocyclic ring. The polymer material has the following general chemical formula: ##STR1## in which: X represents the group constituted by sulphur and selenium; R.sub.1 and R.sub.2 are chosen from the group constituted by hydrogen, and by the alkyl, alkoxyl, and hydroxyl groups; and n is the degree of polymerization. Such materials can be made conductive by adding a doping agent, and they can then be used for manufacturing electrodes, junctions, Schottky barriers, etc.
摘要:
A family of negative resins, capable of undergoing crosslinking under the effect of more or less energetic photons (gamma radiation, X-rays, ultraviolet or visible light), applicable to the protection of objects against atmospheric agents and to the production of masks of the type used in the production of integrated circuits. The typical compound according to the invention contains at least one substance of which the chemical formula comprises a thiirane ring: ##STR1## such as 2,3-epithiopropyl methacrylate copolymerized with a vinyl monomer, such as methyl methacrylate. Crosslinking is facilitated by photoinitiators, such as aryl diazonium and aryl iodonium salts liberating Lewis acids. By selecting the photoinitiator, it is possible to act on the spectral region where irradiation is effective.
摘要:
A family of negative resins, capable of undergoing crosslinking under the effect of more or less energetic photons (gamma radiation, X-rays, ultraviolet or visible light), applicable to the protection of objects against atmospheric agents and to the production of masks of the type used in the production of integrated circuits. The typical compound according to the invention contains at least one substance of which the chemical formula comprises a thiirane ring: ##STR1## such as 2,3-epithiopropyl methacrylate copolymerized with a vinyl monomer, such as methyl methacrylate. Crosslinking is facilitated by photoinitiators, such as aryl diazonium and aryl iodonium salts liberating Lewis acids. By selecting the photoinitiator, it is possible to act on the spectral region where irradiation is effective.
摘要:
A process rendering certain electron masking resins more sensitive or rendering polymers which are unsufficiently sensitive to electrons suitable for industrial utilization, in particular for application to electron masking, a method which employs scanning with a very fine electron beam controlled by the computer. The process involves electron irradiation at low dose levels, sufficient however to create free radicals, followed by diffusion of an appropriate copolymerizing monomer by grafting to the initial polymeric chain opened by the irradiation process. The solubility of the copolymer vis-a-vis certain solvents is selective, enabling the masks to be developed.
摘要:
A family of negative resins, capable of undergoing crosslinking under the effect of more or less energetic photons (gamma radiation, X-rays, ultraviolet or visible light), applicable to the protection of objects against atmospheric agents and to the production of masks of the type used in the production of integrated circuits. The typical compound according to the invention contains at least one substance of which the chemical formula comprises a thiirane ring: ##STR1## such as 2,3-epithiopropyl methacrylate copolymerized with a vinyl monomer, such as methyl methacrylate. Crosslinking is facilitated by photoinitiators, such as aryl diazonium and aryl iodonium salts liberating Lewis acids. By selecting the photoinitiator, it is possible to act on the spectral region where irradiation is effective.
摘要:
A dielectric thin layer consisting of polymerized perfluoro-2-butene:(C F.sub.3 -C F=C F-C F.sub.3).sub.npresenting very good characteristics for production of single or multi-layer capacitors, obtained with a rapid deposition by glow discharge in an a.c. electrical field. The glow discharge is carried out in the gaseous phase of perfluoro-2-butene under highly reduced pressure and an a.c. voltage of 300 volts, the maximum rate of layer formation (0.7 micron per minute) being obtained for a frequency of 13.56Mc/s, at a temperature of 0.degree. C. under a pressure of 0.1 Torr when the useful power of the glow discharge is of 5 to 10 watts.
摘要:
A method of manufacturing an electron-sensitive resin capable of constituting the material of an optical waveguide having a width of the order of 1 micron and transmission loss lower than 2 db/cm, is provided. The method comprises, carried out under conditions of extremely high purity, the hydrolysis of trichlorosilane, to give phenylsilanetriol, the preparation of a benzenic collodion of this product and then the polymerization in the hot state of a phenylsilanetriol solution, and the conversion of the resultant polymer into the polyphenylsiloxanol which is fractionated by successive extremely fine filtering operations carried out upon a solution of this product, into batches having different degrees of polymerization, each of them fitting a typical optical waveguide.
摘要:
A high precision silica coating, is provided. A thin film of a resin, from the polysiloxane group, for instance polyvinylsiloxane, is irradiated by 10,000 electron-volts. The resin converts in an insoluble product in the areas exposed according a predetermined pattern. After a heat treatment in oxidizing atmosphere, the remainder of the film is eliminated.
摘要:
The invention pertains to a method for metallic coating according to which the fiber is made to pass through a bath of molten metal. To prevent unevennesses in coating, caused by turbulence, a depression is made above the bath.The invention also pertains to a device by which the method is applied. The fiber goes vertically through a pot containing the molten metal above which the depression is made.The invention can be used to make optic fibers of greater mechanical strength.